Blender .STL exports are too small when imported in Sli3er
By default, 1 Blender unit = 1 mtr, as evidenced by default gravity value in the scene settings.

You could try setting the scene unit to Centimeters (1 unit = 1cm), then scale accordingly. Make sure to enable "Scene Units" in STL export.

For me, leaving the scene at blender units and for STL export enabling "Scene Units" and setting the scale to 10 works fine. For me. For me, this equates to 1 unit = 1cm